I was rather surprised that Microsoft actually made a client for Windows Live Mesh for Mac OSX Snow Leopard! This is especially surprising since Ubuntu One is Ubuntu only. At least Dropbox lets me synchronize across all platforms. Previously I was using MacFUSE/FUSE Userland sshfs mounting for my Dreamhost backup space.

2GB Free – Dropbox – Mac OSX, Linux, Windows

5GB Free – Windows Live Mesh – Windows & Mac OSX, however the icon stays in the dock which is rather annoying. The menubar icon is the control for Mesh, so the dock icon is extraneous.

2GB Free – Ubuntu One – Ubuntu only, but integrated with Ubuntu 9.10+’s file manager. Since I was reformatting my laptop quite often to try new variants, this let me save important things such as bookmarks or how to get the proprietary Nvidia drivers to work with the Xorg.conf.

I recommend Dropbox because it works on the three platforms I use the most and is often easier than setting up a shared folder on the network.